# Von Pydantic v1 zu Pydantic v2 migrieren { #migrate-from-pydantic-v1-to-pydantic-v2 }

Wenn Sie eine ältere FastAPI-App haben, nutzen Sie möglicherweise Pydantic Version 1.

FastAPI Version 0.100.0 unterstützte sowohl Pydantic v1 als auch v2. Es verwendete, was auch immer Sie installiert hatten.

FastAPI Version 0.119.0 führte eine teilweise Unterstützung für Pydantic v1 innerhalb von Pydantic v2 (als `pydantic.v1`) ein, um die Migration zu v2 zu erleichtern.

from .v2 import RequiredParam as RequiredParam
from .v2 import Undefined as Undefined
from .v2 import UndefinedType as UndefinedType
from .v2 import Url as Url
from .v2 import Validator as Validator
from .v2 import _regenerate_error_with_loc as _regenerate_error_with_loc
from .v2 import copy_field_info as copy_field_info
from .v2 import create_body_model as create_body_model
from .v2 import evaluate_forwardref as evaluate_forwardref

from .param_functions import File as File
from .param_functions import Form as Form
from .param_functions import Header as Header
from .param_functions import Path as Path
from .param_functions import Query as Query
from .param_functions import Security as Security
from .requests import Request as Request
from .responses import Response as Response
from .routing import APIRouter as APIRouter

from fastapi.exceptions import FastAPIDeprecationWarning, PydanticV1NotSupportedError
from pydantic import BaseModel
from pydantic.fields import FieldInfo
from typing_extensions import Literal

from ._compat import v2

if TYPE_CHECKING:  # pragma: nocover
    from .routing import APIRoute

# Cache for `create_cloned_field`
_CLONED_TYPES_CACHE: MutableMapping[type[BaseModel], type[BaseModel]] = (
    WeakKeyDictionary()

from typing import Union

from fastapi import FastAPI, UploadFile
from fastapi._compat import (
    Undefined,
    is_uploadfile_sequence_annotation,
)
from fastapi._compat.shared import is_bytes_sequence_annotation
from fastapi.testclient import TestClient
from pydantic import BaseModel, ConfigDict
from pydantic.fields import FieldInfo

from .utils import needs_py310


def test_model_field_default_required():

import types
import typing
import warnings
from collections import deque
from collections.abc import Mapping, Sequence
from dataclasses import is_dataclass
from typing import (
    Annotated,
    Any,
    Union,
)

from fastapi.types import UnionType
from pydantic import BaseModel
from pydantic.version import VERSION as PYDANTIC_VERSION
from starlette.datastructures import UploadFile
from typing_extensions import get_args, get_origin

import warnings
from collections import deque
from dataclasses import dataclass
from datetime import datetime, timezone
from decimal import Decimal
from enum import Enum
from math import isinf, isnan
from pathlib import PurePath, PurePosixPath, PureWindowsPath
from typing import Optional, TypedDict

import pytest
from fastapi._compat import Undefined
from fastapi.encoders import jsonable_encoder

from collections.abc import Mapping
from typing import (
    Annotated,
    Any,
    BinaryIO,
    Callable,
    Optional,
    TypeVar,
    cast,
)

from annotated_doc import Doc
from pydantic import GetJsonSchemaHandler
from starlette.datastructures import URL as URL  # noqa: F401
from starlette.datastructures import Address as Address  # noqa: F401
from starlette.datastructures import FormData as FormData  # noqa: F401

from datetime import datetime, timezone

from fastapi import FastAPI
from fastapi.testclient import TestClient
from pydantic import BaseModel


def test_pydanticv2():
    from pydantic import field_serializer

    class ModelWithDatetimeField(BaseModel):
        dt_field: datetime

        @field_serializer("dt_field")
        def serialize_datetime(self, dt_field: datetime):

from typing import Annotated, Any
from unittest.mock import Mock, patch

from fastapi import Depends, FastAPI
from fastapi.testclient import TestClient

from docs_src.dependencies.tutorial010_py39 import get_db


def test_get_db():
    app = FastAPI()

    @app.get("/")
    def read_root(c: Annotated[Any, Depends(get_db)]):
        return {"c": str(c)}

    client = TestClient(app)

    dbsession_mock = Mock()